Pump



March 29, 1945.. F RUTHVEN 2,371,846

PUMP

Filed March 26, 1943 F/g I F/ 2 INVENTOR.

ALBERT I; fil/THVE/V BY WH/TEHEAD J- VOGL H1; Af/ornG/J Patented Mar. 20, 1945 Albert F. Ii-uthven, Lincoln, Nebn, assignor to Ruthven Side-Pocket Dam Corporation, Lincoln, Nebn, a corporation of Colorado Application-March 26, 1943, Serial'No. 480,597 (Cl. 1'03--204) 2 Claims.

This invention relates to improvement in pumps and especially to pumps having hollow cylindrical plungers reciprocable within pump barrels and usually operated at high speeds,

Objects of the invention are to provide, in a pump of the class described, (a) improved means forgetting lubrication to the adjacent surfaces of the barrel and plunger; (b) improved means for eliminating or substantially reducing injury to the adjacent surfaces of the barrel and plunger resulting from sand or other solids settled or accumulated from the liquid being pumped, and (c) an improved structure in the wall of the plunger which shall, coincidentally, accomplish,

or contribute to the accomplishment of, both of these objects.

'With these, and other objects in View, all of which shall more fully hereinafter appear, the invention comprises certain novel constructions,

combinations and arrangements of parts as hereinafter described and claimed and as illustrated, in preferred embodiment, in the accompanying drawing in which I I I Fig. 1 is a longitudinal section of a fragment of a pump barrel with a plunger therein, the plunger being shown partly in elevation and partly in section, the sectioned portion disclosing a check valve carried by the plunger at its lower end.

Fig. 2 is a bottom view of the structure shown at Fig. 1, the barrel, however, being shown in full lines.

Fig. 3 is a sectional view on line3-3 of Fig. 1.

Fig. 4 is an enlarged and somewhat exaggerated I view of the bucket portion of Fig. 3.

A plunger, construed according to this invention, may be installed in a cylindrical barrel of any pump, and, accordingly, I have disclosed in the drawing only a portion of a conventional bare rel in having reciprocably positioned therein a hollow cylindrical plunger I I, only sufiicient clearance being provided between the barrel, and the plunger to avoid friction, such clearance being preferably between and A000 Of an inch.

Any suitable check valv is provided at the lower end of the plunger, the valve assembly here illustrated being convenient for this purpose and comprising a base l2 having a central bore l3 at the top of which bore is a valve seat I! for a ball valve I5. The base has a threaded engagement with the'lower end of the plunger as at [B whereby, when assembled, the plunger and base become a unit. The base is provided withan upstanding cage or runway I! for ball I an'd'the usual sucker rod I8 is attached to the top of the cage whereby continuous operation of such a pump, at high the plunger and valve assembly are reciprocated as aunit by the sucker rod.

It will be understood that as the plunger is lowered, liquid, from the lower part of the barrel, enters the interior of the plunger through the valve, and that as the plunger is raised the valve closes and the liquid within the plunger is lifted in the usual manner.

' The clearance between the barrel and plunger permits the entrance of a film of liquid between the walls of the barrel and plunger which film acts as a lubricant.

Under ordinary operative conditions the fluid being pumped carries some sand or similar solids hereinafter included in the term sand. Durin speeds, the sand is carried .by the rising column of liquid and does not settle in or around the plunger nor does any appreciable amount find its way into the clearance between the walls of the barrel and plunger. When, however, the pump is not operating, sand, from the column of liquid above the plunger, settles onto the top edge to the plunger and against the wall of'the barrel and bridges the top of the'clearance space between the walls of the plunger and barrel. When the pump is again started, this accumulated sand tends to work down into the clearance space and score the walls of the barrel and plunger. This is especially true when the plunger has been stopped at the bottom of its stroke so that, upon again starting the pump, the first movement of the plunger is upward. Also if the plunger has come to rest in a slightly off-ce'nter position so that the top of the plunger lies against the barrel wall on oneside and correspondingly enlarges the clearance space on the opposite side, the danger of sand working down between the walls is, obviously, increased.

I am aware that efforts have heretoforebeen made to collect and remove the sand which finds its way from above intoIthe clearance space and that for that purpose annular grooves have been.

plished by the improvement now more specifically described.

Generally, the invention consists in grooving and perforating the wall of the plunger, the groove being provided to catch any sand which finds its way down around the outside of the plunger and also to furnish a channel for circulation of fluid, and in perforating the wall of the plunger at the bottom of the groove, thereby forming communication between the groove and the interior of the plunger whereby fluid may circulate in the groove and, in either direction, between the groove and the plunger interior.

Two such grooves are illustrated and are indicated by H! and [9a respectively. Two sets of conduits are illustrated in each of the grooves. The sets are designated as 20 and 2| respectively. Two grooves are not essential but are preferable; More than two may be used and, in case of lon plungers, more would be desirable. It will be noted that the conduits or orifices 20 are radial while those designated as 2| are angled, relative to the radius of the plunger. The use of both radial and angled conduits is preferable but the angled orifices are Ofgreater importance as will clearly appear hereinafter. These conduits 20 and 2| are all horizontal, that is to say, their axes lie in a plane perpendicular to the axis of the plunger as clearly shown atFig. 3. This horizontal positioning of the conduits is important in order to reduce to a minimum the entrance into the conduits of sand, moving up or down in the center of the plunger. Such conduits opening either upwardly or downwardly into the plunger chamber would tend to catch sand moving up or down in the chamber and conduct it liquid which will come through orifices 20 and 2! from the inside of the plunger, while the plunger is being raised, and enable such liquid to circulate in the groove and contact and lubricate the wall of the barrel and seep down in the clearance for lubricating the walls of the plunger and barrel. For accomplishing this lubricating function the most emcient location of the groove is at or near the midseotion of the plunger. This is especially true in the'case of long plungers, because the longer the plunger the greater is the danger of.

lack of lubrication at the central part of the plunger if the lubricating fluid can enter the clearance only at the top and bottom of the plunger. v v

It, therefore, appears that for the sand catching purpose alone, the groove should be near the top of the plunger while for the lubrication purpose alone, the. groove should be near or a little above the middle of the plunger.

With short plungers both purposes can be accomplished with substantial efficiency by providing one groove somewhat above the middle of the plunger.

In the case of long plungers it is preferable to provide one groove near the top, and another near the middle, of the plunger. In such case the upper groove will collect most of the sand and will contribute some needed lubrication, while the lowergroove will collect any sand which may have escaped the upper groove and will furnish lubrication to the midsection of the plunger and adjacent barrel wall.

- The arrangement of the orifices 20 and 2! relative to the groove is of great importance. When the plunger is being lifted the fluid will flow from the interior of the plunger outwardly into the groove, for lubrication as above described. This outflowing liquid also serves another purpose, namely, agitation of the liquid in the groove whereby to prevent the settling and packing therein of the collected sand. For this reason the orifices 2B and 21 are positioned in the lower portion of the groove bottom, that is to say, near the lower side of the groove on which lower side the sand would normally collect and pack. By such low positioning of the orifices the liquid is caused to be ejected therefrom directly into the area in which the sand would normally settle and pack and such election tends to prevent such settling and packing.

In this connection, the angular arrangement of the orifices 2| is most important. By reason of such angularity the liquid passing through the orifices 2| emerges therefrom into the groove in a direction which causes a circulatory movement of the liquid in the groove, thus effectively preventing settling and packing of the sand. While the angularity of the conduits 2i is of primary importance, it is alsoimportant that some of the conduits, as indicated at 20, be radial because such radial conduits will more effectively collect, from the circulating streamin the groove, the sand particles and lead them out into the main stream in the plunger chamber and thence-out of the pump.

When the plunger is forced down into the liquid in the lower part of the barrel such liquid is forced into the plunger not only through .the valve but also between the lower portion of the walls of the plunger and barrel and thence into the groove and through the orifices 20 and 2|. During this movement the sand-carrying liquid in the groove is forced-through the orifices 20 and 2| and into the rising column of liquid and thence out of the pump.

Thus, while each upward stroke of the plunger tendsto gather into the groove any sand which has worked down between the walls, the liquid flowing out through the orifices, maintains a circulation and agitation in the groove and keeps the sand in suspension and the succeeding downward stroke of the plunger forces the sand laden liquid from the groove back throughthe orifices into the water column within the plunger and by this action, repeated with each cycle of movement of the plunger, the present invention, promptly upon resumption of operation of the pump, eliminates any sand which may have accumulated at the top of the plunger during the preceding inoperative period.

While I have illustrated and described certain details of structure in and associated with the illustrated embodiment of my invention, the invention is not, and I am not .to be,'limited to such details.

I claim:

1. In a, pump including a barrel and a hollow cylindrical plunger reciprocable in the barrel, the combination of an annular groove in the outer wall of the plunger and conduits in the plunger wall opening into the groove and into the interior of the plunger, said conduits lying in a plane perpendicular to the axis of the plunger, some of said conduits being radial of the plunger and others being angular, relative to the radii of the plunger.

2. In a pump including a barrel and a hollow cylindrical plunger reciprocable in the barrel, the combination of an annular groove in the outer wall of the plunger, said groove having a horizontal lower side, and conduits leading from the interior of the plunger into said groove adjacent said lower side, said conduits lying in a. plane perpendicular to the axis of the plunger and some of said conduits being radial of the plunger and others being angular, relative to the radii of the plunger.

ALBERT F. RUTHVEN. 

